China Civil UAV Theory Questions — Questions 561–570

Cumulonimbus clouds vary greatly in scale: small when newly formed, larger when mature, so option C is wrong.

Higher temperature means lower air density and less lift, so all aircraft service ceilings decrease.

Wing and tail icing distorts the airfoil and increases both friction drag and pressure drag, so option B is incorrect.

Tropospheric temperature decreases with height, ruling out option A; temperature and humidity are unevenly distributed horizontally (affected by the surface), ruling out option B; “convection” means air has strong vertical mixing, so option C is correct.

Study note: when two short options and one long option appear, choose the longest. Wind shear can be caused by fronts, inversion layers, thunderstorms, terrain, and other factors, and may occur at any altitude in the atmosphere where wind direction or speed changes.

The Coriolis force deflects airflow to the right in the Northern Hemisphere and to the left in the Southern Hemisphere.

Study note: for fronts, look at temperature. A front is the interface between two air masses of different properties. Option A is wrong (it is not a wind convergence interface); option C is wrong (the line where the wind field meets the ground is the frontal line).

Over large water bodies and densely vegetated areas, daytime warming is slow, air sinks, producing a sinking effect that lands the aircraft short of the expected touchdown point; over unvegetated terrain, air rises, producing a floating effect that carries the aircraft past the touchdown point.

Dynamic convective lifting force is caused by mechanical lifting, such as a mountain windward slope lifting air; option B is horizontal motion; option C is a thermal cause.

At lower temperatures, battery discharge performance drops, reducing UAV endurance. At higher temperatures, batteries may lose efficiency or even be damaged from overheating.